Today, analogue media are gradually being replaced by digital media. In the case of audio this transition has already largely taken place, and it is well underway for image, video, graphics animation and other media. As these media become digital and the capability/cost ratio of computing resources continues to increase, new users and markets for digital media production are opening up. Of particular relevance to this invention are emerging markets for casual media production and especially casual video production, i.e. cases where the high cost of professional video production would preclude its use and where, until recently, the cost of the necessary equipment was too high. These include home video production (e.g. of holidays, weddings, etc), some informal corporate uses (e.g. internal communications and team-building), use by societies and other organizations, etc.
The concept of casual or “desktop” video production has existed for about a decade, but widespread adoption has been held back by a number of problems. These include:    1. Problems of technical infrastructure: inconvenience and loss of quality when digitizing video from a camera, limited hard disk space, insufficient processing power, etc.    2. The lack of convenient, low-cost distribution mechanisms: until recently the only widespread formats have been videotapes, but the cost and time involved in duplication and distribution preclude many potential applications.    3. The time and expertise required to make acceptable-quality productions, particularly at the stage of editing and “post-production”.
The first and second of these problems are today disappearing thanks to technologies such as DV cameras, the IEEE 1394 (“Firewire”) interface and video distribution on the world-wide web.
This invention attempts to address the third problem, allowing automated or semi-automated editing of digital media, particularly video.
Today, the main tool used for editing video is the “Non-Linear video Editor” or NLE. These are computer programs which adopt many paradigms from conventional editing methods such as film cutting and linear dub-editing using video tape machines. They employ manual methods of editing which are well suited to scenarios where the user is experienced and the desired result is a high-quality video production. There are many products of this type including Premiere from Adobe Inc., and iMovie from Apple Inc.
The NLE is a considerable advance on earlier technology, yet there remain many scenarios in which the user is not a media professional, in which professional quality is not essential, or in which it is necessary to edit material very quickly. Even NLEs which claim to be aimed at non-professionals have a significant learning curve and require substantial time to produce acceptable productions. It is generally accepted that in typical cases a user will have to spend one hour in order to create one minute of output video, in other words a ratio of 60:1 of production time to playback duration. It is one of the goals of the current invention to reduce this ratio dramatically through automation, to the point where in some cases acceptable results can be produced without any user intervention.
There also exist several tools which allow a user to create productions involving the real-time display of images and text synchronized to an audio track. These include animation tools (e.g. Flash from Macromedia Inc.), slideshow tools (e.g. PowerPoint from Microsoft Inc.) and authoring tools for streaming media (e.g. RealPlayer from Real Networks Inc.). But once again, users often find that they need to spend hours in order to produce a simple production lasting a few minutes.